Re: postgres_fdw: perform UPDATE/DELETE .. RETURNING on a join directly

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Fri, Feb 9, 2018 at 1:33 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>>> Me neither. I just ran the postgres_fdw regression tests 713 times in
>>> a row without a failure. Tom, since you seem to be able to reproduce
>>> the problem locally, could you have a look at this proposed fix?

>> I'm a bit busy, but AFAICS it's just a timing thing, so try inserting
>> a sleep. The attached is enough to reproduce rhinoceros' results
>> for me.

> Not for me, but when I pushed the pg_sleep up to 180 seconds, then it failed.

> With the proposed patch, it passes repeatedly for me with no sleep,
> and also passes for me with the sleep. So I guess I'll commit this
> and see what the buildfarm thinks.

FWIW, I ran a thousand cycles of postgres_fdw installcheck without seeing
further problems. So this fixes it at least for my configuration.
However, jaguarundi still shows a problem:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=jaguarundi&dt=2018-02-10%2008%3A41%3A32

(previous run similar, so it's semi-reproducible even after this patch).
jaguarundi uses -DCLOBBER_CACHE_ALWAYS, so you might try a few repetitions
with that.

regards, tom lane